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The genus Dirphys Howard 1914 syn. n. is synonymized with Encarsia Förster, and treated as a species-group of Encarsia, referred to henceforth as the Encarsia mexicana species-group. The monophyly of Encarsia is discussed in relation to Dirphys. The new synonymy is based on phylogenetic analyses of the nuclear ribosomal 28S-D2 gene region (43 taxa, 510 bp). The Encarsia mexicana species-group is recovered as strongly monophyletic within Encarsia. All species of the Encarsiamexicana species-group are revised. The group includes six previously described species, and fourteen newly described species. All species are described (or redescribed) and illustrated. Detailed distributional data, and, where available, plant associate and host records are provided for all species. Encarsia myartsevae Kresslein and Polaszek nom. nov. is here proposed as a replacement name for Encarsia mexicana Myartseva, now preoccupied by Encarsia mexicana (Howard). A dichotomous identification key, supplemented by an online multiple-entry key, is provided for all species.

The genus Dirphys Howard is synonymized with Encarsia Förster syn. n. and treated as a species-group of Encarsia, referred to henceforth as the Encarsia mexicana species-group. The monophyly of Encarsia is discussed in relation to Dirphys. The new synonymy is based on phylogenetic analyses of the nuclear ribosomal 28S-D2 gene region (43 taxa, 510 bp). The Encarsia mexicana species-group is recovered as strongly monophyletic within Encarsia. All species of the Encarsia mexicana species-group are revised. The group includes six previously described species, and fourteen newly described species. All species are described (or redescribed) and illustrated. Detailed distributional data, and, where available, plant associate and host records are provided for all species. Encarsia myartsevae Kresslein & Polaszek nom. nov. is here proposed as a replacement name for Encarsia mexicana Myartseva, now preoccupied by Encarsia mexicana (Howard). A dichotomous identification key, supplemented by an online multiple-entry key, is provided for all species.

The aims of this paper are to debate and raise awareness about the use of systematic, interconnected approaches for biodiversity collection curation by exploring the multi-disciplinary relevance of quality management tools developed by clinical biobanks. An appraisal of their best practices indicated the need for improved sample and process chain annotation as a significant number of historical collections used in medical research were of inadequate quality. This stimulated the creation of a new discipline, biospecimen science to develop quality management tools for clinical biobanks, two of which, Biospecimen Reporting for Improved Study Quality (BRISQ) and the Standard PRE-analytical Code (SPREC) report critical information about samples and process chain variables. Unprecedented advances in molecular-genetic and in silico technologies applied across the tree of life require international conservation networks to generate and share knowledge. This is used in biodiversity and systematics research, and to...

An up to date dataset of the Insect Pollinators Initiative, A multi-institution initiative with the NHM, BBSRC and The University of Edinburgh. The archive is held at the Natural History Museum, London. Current dataset approximately 42,500.

Together, Indian plus Seychelles caeciliid caecilian amphibians (Gymnophiona) constitute approximately 10% of the extant species of this order. A molecular phylogenetic analysis of all but one (or two) nominal species (16, in five genera) is presented based on mitochondrial (12S, 16S, cytb, cox1) and nuclear (RAG1) sequence data. Results strongly support monophyly of both Seychelles and peninsular Indian caeciliids, and their sister-group status. Within the Indian caeciliids, Indotyphlus and Gegeneophis are monophyletic sister genera. The phylogenetic position of Gegeneophis ramaswamii, Gegeneophis seshachari, and Gegeneophis carnosus are not well resolved, but all lie outside a well-supported clade of most northern Western Ghats Gegeneophis (madhavai, mhadeiensis, goaensis, danieli/nadkarnii). Most nominal species of Indian caeciliid are diagnosed by robust haplotype clades, though the systematics of G. carnosus-like forms in northern Kerala and southern Karnataka requires substantial further investigation. For the most part, Indian caeciliid species comprise narrowly distributed, allopatric taxa with low genetic diversity. Much greater geographic genetic diversity exists among populations referred to G. seshachari, such that some populations likely represent undescribed species. This, the first phylogenetic analysis of Indian caeciliids, generally provides additional support for recent increases in described species (eight since 1999), and a framework for ongoing taxonomic revision.

Morphological evidence suggests harpacticoid copepods have recurrently entered into symbiosis with other crustaceans but only members of the family Cancrincolidae have successfully made the transition from marine habitats to semiterrestrial hosts. Cancrincolids are primarily amphi-Atlantic in distribution (with one outlier in the western Pacific) and typically inhabit the gill chambers of grapsoidean land crabs belonging to the families Grapsidae, Sesarmidae, Varunidae and Gecarcinidae. Morphologically, they are difficult to place because they exhibit unusual autapomorphies and the shared derived characters claimed to unite them with the primitively marine Ameiridae are equivocal. Both maximum parsimony and Bayesian inference solutions based on SSU rDNA gene sequences show topological congruence in placing the Cancrincolidae within the Ameiridae and in firmly resolving it as the sistergroup of taxa that have been reported as obligate or commensal associates of crayfish. This relationship is further supported by swimming leg sexual dimorphism and mandibular palp morphology. Morphological comparison with ameirid copepods revealed the majority of synapomorphies previously proposed in support of cancrincolid monophyly and familial distinctiveness can be attributed to heterochrony. The progressive evolution of cancrincolid associates appears to be largely concordant with the sequential adaptation to terrestriality by their grapsoidean hosts. The current amphi-Atlantic distribution of Cancrincola may suggest its possibly free-living ancestor had already assumed a virtually continuous distribution along the northern seaboard of Gondwana prior to the opening of the South Atlantic during the early Cretaceous, implying symbiotic relationships were established only much later when grapsoidean crabs started to emerge, radiate and diversify in the mid-Tertiary (15–35 mya). The adoption of semi-terrestriality in cancrincolid copepods can be viewed as yet another independent attempt (incursion) to colonize low-salinity environments by members of the family Ameiridae. The possible sistergroup relationships of the Ameiridae and the position of the genus Argestigens Willey are discussed.

The monophyly and phylogenetic relationships of the Cephalaspidea sensu lato (sensu Burn and Thompson 1998) have been investigated by means of Bayesian, parsimony and distance analyses of nuclear (18S rRNA and 28S rRNA) and mitochondrial cytochrome oxidase I (COI) genes. Results revealed the presence of three monophyletic groups among the Cephalaspidea s. l. (i) Architectibranchia (sensu Haszprunar 1985, in part: including Acteonidae and Aplustridae, but excluding Diaphanidae), (ii) Cephalaspidea including Diaphanidae but not Runcinidae (both previously of uncertain systematic affinity), and (iii) Runcinacea. The monophyly of the architectibranch families Acteonidae (represented by Acteon and Pupa) and Aplustridae (Hydatina and Micromelo); of the runcinacean family Runcinidae (Runcina); and of the cephalaspidean families Aglajidae (Chelidonura, Aglaja, Odontoglaja, Navanax and Philinopsis), Bullidae (Bulla), Gastropteridae (Siphopteron and Sagaminopteron), Haminoeidae (Atys, Haminoea, Phanerophthalmus and Smaragdinella, but not Ventomnestia), and Retusidae (Retusa and Pyrunculus, but not Volvulella) is suggested. The families Scaphandridae (Scaphander) and Rhizoridae (Volvulella) are reinstated as valid. A new phylogenetic classification of the Cephalaspidea is proposed.

We sequenced and annotated the complete mitochondrial (mt) genome of the priapulid Priapulus caudatus in order to provide a source of phylogenetic characters including an assessment of gene order arrangement. The genome was 14,919 bp in its entirety with few, short non-coding regions. A number of protein-coding and tRNA genes overlapped, making the genome relatively compact. The gene order was: cox1, cox2, trnK, trnD, atp8, atp6, cox3, trnG, nad3, trnA, trnR, trnN, rrnS, trnV, rrnL, trnL(yaa), trnL(nag), nad1, -trnS(nga), -cob, -nad6, trnP, -trnT, nad4L, nad4, trnH, nad5, trnF, -trnE, -trnS(nct), trnI, -trnQ, trnM, nad2, trnW, -trnC, -trnY; where '-' indicates genes transcribed on the opposite strand. The gene order, although unique amongst Metazoa, shared the greatest number of gene boundaries and the longest contiguous fragments with the chelicerate Limulus polyphemus. The mt genomes of these taxa differed only by a single inversion of 18 contiguous genes bounded by rrnS and trnS(nct). Other arthropods and nematodes shared fewer gene boundaries but considerably more than the most similar non-ecdysozoan.

The phylogenetic relationships of 46 echinoids, with representatives from 13 of the 14 ordinal-level clades and about 70% of extant families commonly recognized, have been established from 3 genes (3,226 alignable bases) and 119 morphological characters. Morphological and molecular estimates are similar enough to be considered suboptimal estimates of one another, and the combined data provide a tree that, when calibrated against the fossil record, provides paleontological estimates of divergence times and completeness of their fossil record. The order of branching on the cladogram largely agrees with the stratigraphic order of first occurrences and implies that their fossil record is more than 85% complete at family level and at a resolution of 5-Myr time intervals. Molecular estimates of divergence times derived from applying both molecular clock and relaxed molecular clock models are concordant with estimates based on the fossil record in up to 70% of cases, with most concordant results obtained using Sanderson's semiparametric penalized likelihood method and a logarithmic-penalty function. There are 3 regions of the tree where molecular and fossil estimates of divergence time consistently disagree. Comparison with results obtained when molecular divergence dates are estimated from the combined (morphology + gene) tree suggests that errors in phylogenetic reconstruction explain only one of these. In another region the error most likely lies with the paleontological estimates because taxa in this region are demonstrated to have a very poor fossil record. In the third case, morphological and paleontological evidence is much stronger, and the topology for this part of the molecular tree differs from that derived from the combined data. Here the cause of the mismatch is unclear but could be methodological, arising from marked inequality of molecular rates. Overall, the level of agreement reached between these different data and methodological approaches leads us to believe that careful application of likelihood and Bayesian methods to molecular data provides realistic divergence time estimates in the majority of cases (almost 80% in this specific example), thus providing a remarkably well-calibrated phylogeny of a character-rich clade of ubiquitous marine benthic invertebrates.

Aim This study aimed to test monophyly and geographical boundaries in five marine intertidal snail species from the central Indo-West Pacific. We tested the prediction that phylogenetic breaks between the Indian and Pacific Ocean basins should be more pronounced in continental than oceanic settings, and sought common geographical patterns of interspecific boundaries and intraspecific phylogenetic breaks in the region. Location The tropical seas of the Indo-West Pacific. Methods We sequenced over 1200 bp of the mitochondrial cytochrome oxidase subunit I gene (COI) from 18–92 individuals sampled from throughout the ranges of each of five species of Echinolittorina (Littorinidae): three members of the Echinolittorina trochoides species complex; Echinolittorina reticulata; and Echinolittorina vidua, together with sister species, in order to test species boundaries. In addition, 630 bp of the nuclear 28S rRNA gene were sequenced from E. reticulata and its sister Echinolittorina millegrana. Phylogenetic structure was assessed using neighbour-joining and parsimony analyses. Results COI data confirmed species boundaries and geographical distributions for all species except the pair E. reticulata and E. millegrana, which were nevertheless reciprocally monophyletic for 28S rRNA. The species from ecologically ‘continental’ habitats (E. trochoides A and E. vidua, but not E. trochoides B) mostly showed strong interoceanic breaks (with age estimates 0.58–4.4 Ma), while the ecologically ‘oceanic’E. trochoides D and E. reticulata did not. The sister species E. trochoides A and B occupy the shores of the continental shelves of Southeast Asia and Australasia respectively; between them lies the oceanic ‘eastern Indonesian corridor’ occupied by E. trochoides D and E. reticulata. The widespread continental species E. vidua showed a complex pattern of deep division into six haplotype clades with apparently parapatric distributions. Main conclusions Our results show that ecological differences (in this case continental vs. oceanic habitat) influence both intraspecific phylogenetic structure and interspecific boundaries in these snails of intertidal rocky shores. Two of the three species restricted to continental shelves show phylogenetic breaks between the Indian and Pacific Oceans, consistent with vicariant separation during Plio-Pleistocene low sea levels. The two oceanic species do not show breaks, suggesting that they maintained interoceanic connections through the eastern Indonesian corridor. The geographical location of the interspecific boundary between continental E. trochoides A and oceanic E. trochoides D mirrors intraspecific breaks reported in other species. The sister relationship of E. trochoides A and B in Asia and Australasia, respectively, is an example of a ‘marine Wallace's line’ distribution, and we suggest that it is the result of separation of two continental species by a barrier of unsuitable oceanic habitat.

A phylogeny for 21 species of spatangoid sea urchins is constructed using data from three genes and results compared with morphology-based phylogenies derived for the same taxa and for a much larger sample of 88 Recent and fossil taxa. Different data sets and methods of analysis generate different phylogenetic hypotheses, although congruence tests show that all molecular approaches produce trees that are congruent with each other. By contrast, the trees generated from morphological data differ significantly according to taxon sampling density and only those with dense sampling (after a posteriori weighting) are congruent with molecular estimates. With limited taxon sampling, secondary reversals in deep-water taxa are interpreted as plesiomorphies, pulling them to a basal position. The addition of fossil taxa with their unique character combinations reveals hidden homoplasy and generates a phylogeny that is compatible with molecular estimates. As homoplasy levels were found to be broadly similar across different anatomical structures in the echinoid test, no one suite of morphological characters can be considered to provide more reliable phylogenetic information. Some traditional groupings are supported, including the grouping of Loveniidae, Brissidae and Spatangidae within the Micrasterina, but the Asterostomatidae is shown to be polyphyletic with members scattered amongst at least five different clades. As these are mostly deep-sea taxa, this finding implies multiple independent invasions into the deep sea.

1These authors contributed equally to this research. SUMMARY Research into arthropod evolution is hampered by the derived nature and rapid evolution of the best-studied out-group: the nematodes. We consider priapulids as an alternative out-group. Priapulids are a small phylum of bottom-dwelling marine worms; their tubular body with spiny proboscis or introvert has changed little over 520 million years and recognizable priapulids are common among exceptionally preserved Cambrian fossils. Using the complete mitochondrial genome and 42 nuclear genes from Priapulus caudatus ,w e show that priapulids are slowly evolving ecdysozoans; almost all these priapulid genes have evolved more slowly than nematode orthologs and the priapulid mitochondrial gene order may be unchanged since the Cambrian. Considering their primitive bodyplan and embryology and the great conservation of both nuclear and mitochondrial genomes, priapulids may deserve the popular epithet of ‘‘living fossil.’’ Their studyislikely to yield significant new insights into the early evolution of the Ecdysozoa and the origins of the arthropods and their kin as well as aiding inference of the morphology of ancestral Ecdysozoa and Bilateria and their genomes.

In this paper we investigate the utility of the COI DNA barcoding region for species identification and for revealing hidden diversity within the subgenus Trichodagmia and related taxa in the New World. In total, 24 morphospecies within the current expanded taxonomic concept of Trichodagmia were analyzed. Three species in the subgenus Aspathia and 10 species in the subgenus Simulium s.str. were also included in the analysis because of their putative phylogenetic relationship with Trichodagmia. In the Neighbour Joining analysis tree (NJ) derived from the DNA barcodes most of the specimens grouped together according to species or species groups as recognized by other morphotaxonomic studies. The interspecific genetic divergence averaged 11.2% (range 2.8–19.5%), whereas intraspecific genetic divergence within morphologically distinct species averaged 0.5% (range 0–1.2%). Higher values of genetic divergence (3.2–3.7%) in species complexes suggest the presence of cryptic diversity. The existence of well defined groups within S. piperi, S. duodenicornium, S. canadense and S. rostratum indicate the possible presence of cryptic species within these taxa. Also, the suspected presence of a sibling species in S. tarsatum and S. paynei is supported. DNA barcodes also showed that specimens from species that were taxonomically difficult to delimit such as S. hippovorum, S. rubrithorax, S. paynei, and other related taxa (S. solarii), grouped together in the NJ analysis, confirming the validity of their species status. The recovery of partial barcodes from specimens in collections was time consuming and PCR success was low from specimens more than 10 years old. However, when a sequence was obtained, it provided good resolution for species identification. Larvae preserved in ‘weak’ Carnoy’s solution (9:1 ethanol:acetic acid) provided full DNA barcodes. Adding legs directly to the PCR mix from recently collected and preserved adults was an inexpensive, fast methodology to obtain full barcodes. In summary, DNA barcoding combined with a sound morphotaxonomic framework provides an effective approach for the delineation of species and for the discovery of hidden diversity in the subgenus Trichodagmia.